Detector for x-ray computer tomography scanners
A detector for x-ray computer tomography scanners, includes a number of adjacent detector lines extending in an x direction, whereby each detector line is formed from a multitude of adjacent scintillator elements. In order to increase the resolution in the z direction and to simplify the design of the detector, the surface of the scintillator elements are partially covered, which further serves to reduce the size of the aperture in the z direction.
Latest Siemens Aktiengesellschaft Patents:
- System and method for streaming measurement data
- Generation of test models from behavior driven development scenarios based on behavior driven development step definitions and similarity analysis using neuro linguistic programming and machine learning mechanisms
- Knowledge graph for real time industrial control system security event monitoring and management
- Clamping circuit in a rectifier with more than two potentials provided on the output side
- Computer
This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/DE03/00739 which has an International filing date of Mar. 7, 2003, which designated the United States of America and which claims priority on German Patent Application number DE 102 11 948.1 filed Mar. 18, 2002, the entire contents of which are hereby incorporated herein by reference.
FIELD OF THE INVENTIONThe invention generally relates to an x-ray computer tomography scanner comprising a detector.
BACKGROUND OF THE INVENTIONA computer tomography scanner that includes a detector is known, for example, from DE 195 02 574 A1. The detector of the known x-ray computer tomography scanner is a so-called multi-line detector. It includes a plurality of detector lines that are arranged in the direction of the axis of an object that is to be irradiated, for example, a patient. The aforementioned axis is also referred to as the z axis. In an x direction running perpendicular to the z axis, each detector line consists of a plurality of adjacent scintillator elements.
In the z direction, the resolution of such a multi-line detector is a function of the height of the scintillator elements in the z direction. For technical reasons, the height of the scintillator elements cannot be reduced at will. For this reason the resolution of conventional multi-line detectors in the z direction is limited.
SUMMARY OF THE INVENTIONAn object of an embodiment of the invention is to reduce or even eliminate at least one of the disadvantages according to the prior art. In particular, one aim, in one embodiment, is to disclose an x-ray computer tomography scanner including a detector that is as simple as possible and inexpensive to produce, with which an increased resolution is possible in the z direction where there is a set number or height of lines.
According to an embodiment of the invention, a device that partially covers the surface of the scintillator elements is provided, which partially covers the surface of the scintillator elements, for reducing the size of the aperture in the z direction. The step that is suggested allows an increase in the resolution in the z direction, in a simple and inexpensive manner. The proposed solution is universal. Conventional scintillator elements can be used. Retroactive conversion of conventional multi-line detectors is also possible.
Usefully, the device for reducing the size of the aperture is formed from a plurality of parallel adjacent strips, the strips advantageously covering the edges of the scintillator elements that run in the x direction. The proposed features also make it possible to use scintillator elements, the edges whereof have smaller openings in the x direction.
According to a further embodiment, the strips are arranged a predetermined distance Δz apart in the z direction, such that the scintillator elements essentially have the same aperture in the z direction. This makes the manufacture of the detector simpler. Furthermore, the device for reducing the size of the aperture can include transverse strips which cover the edges of the scintillator elements that run in the z direction. Thus the aperture can be reduced in size in the x direction, too. In this case, the edges of the scintillator elements that extend in the z direction no longer have to be of the quality required by the prior art.
The device for reducing the size of the aperture is advantageously formed in one piece in the manner of a surround that is attachable to the detector surface that is formed by the scintillator surfaces. This makes the retroactive conversion of conventional multi-line detectors possible. The surround is designed to be symmetrical with respect to a plane of symmetry that runs perpendicular to the z direction.
According to an advantageous embodiment, the device for reducing the size of the aperture is manufactured from a metal that absorbs X-rays effectively, preferably of lead or tungsten.
Further advantages, features and details of the invention will become evident from the description of illustrated exemplary embodiments given hereinbelow and the accompanying drawings, which are given by way of illustration only and thus are not limitative of the present invention, wherein:
The measuring system rotates around the axis of rotation 7 such that the object 3 is x-rayed at various angles of projection. From the detector signals produced during the above process, a computer 8 calculates an image of the object 3 which is reproduced on a monitor 9.
In
In the embodiment shown in
Exemplary embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
Claims
1. A detector for an X-ray computer tomography scanner, rotatable around an axis of rotation that runs parallel to a first direction, the detector comprising:
- a plurality of adjacent detector lines extending in a second direction, wherein each detector line is formed from a plurality of adjacent scintillator elements and wherein an aperture of each of said scintillator elements for impinging X-rays is provided by a surface that has a length extending in the first direction and a width extending in the second direction; and
- means, which partially covers the surface of the scintillator elements, for reducing the size of the aperture in the first direction, said means for reducing the size of the aperture including a plurality of parallel adjacent strips.
2. Detector according to claim 1, wherein the strips cover the edges of the scintillator elements that run in the second direction.
3. Detector according to claim 2, wherein the strips are arranged in the first direction a predetermined distance apart, such that the scintillator elements essentially have the same aperture in the first direction.
4. Detector according to claim 2, wherein the means for reducing the size of the aperture further includes transverse strips, which cover the edges of the scintillator elements that run in the first direction.
5. Detector according to claim 1, wherein the strips are arranged in the first direction a predetermined distance apart, such that the scintillator elements essentially have the same aperture in the first direction.
6. Detector according to claim 5, wherein the means for reducing the size of the aperture further includes transverse strips, which cover the edges of the scintillator elements that run in the first direction.
7. Detector according to claim 1, wherein the means for reducing the size of the aperture further includes transverse strips, which cover the edges of the scintillator elements that run in the first direction.
8. Detector according to claim 1, wherein the means for reducing the size of the aperture is formed in one piece in the manner of a surround that is attachable to the detector surface that is formed by the scintillator surfaces.
9. Detector according to claim 1, wherein the means for reducing the size of the aperture is manufactured from a metal that absorbs X-rays effectively.
10. Detector according to claim 1, wherein the means for reducing the size of the aperture is manufactured from at least one of lead and tungsten.
11. An X-ray computer tomography scanner, comprising the detector of claim 1.
12. An X-ray computer tomography scanner, comprising:
- a detector, rotatable around an axis of rotation that runs parallel to a first direction, the detector including, a plurality of adjacent detector lines extending in a second direction, wherein each detector line is formed from a plurality of adjacent scintillator elements and wherein an aperture of each of said scintillator elements for impinging X-rays is provided by a surface that has a length extending in the first direction and a width extending in the second direction; and
- a plurality of parallel adjacent strips, which partially cover the surface of the scintillator elements, adapted to reduce the size of the aperture in the first direction.
13. The scanner of claim 12, wherein the strips cover the edges of the scintillator elements that run m the second direction.
14. The scanner of claim 12, wherein the strips are arranged in the first direction a predetermined distance apart, such that the scintillator elements essentially have the same aperture in the first direction.
15. The scanner of claim 12, wherein the detector further includes transverse strips, which cover the edges of the scintillator elements that run in the first direction.
16. The scanner of claim 12, wherein the plurality of parallel adjacent strips are formed in one piece in the manner of a surround that is attachable to the detector surface that is formed by the scintillator surfaces.
17. The scanner of claim 12, wherein the plurality of parallel adjacent strips is manufactured from a metal that absorbs X-rays effectively.
18. The scanner of claim 12, the plurality of parallel adjacent strips are manufactured from at least one of lead and tungsten.
19. A detector, rotatable around an axis of rotation that runs parallel to a first direction, the detector comprising:
- a plurality of adjacent detector lines extending in a second direction, wherein each detector line is formed from a plurality of adjacent scintillator elements and wherein an aperture of each of said scintillator elements for impinging X-rays is provided by a surface that has a length extending in the first direction and a width extending in the second direction; and
- a plurality of parallel adjacent strips, which partially cover the surface of the scintillator elements, adapted to reduce the size of the aperture in the first direction.
4644578 | February 17, 1987 | Paolini |
5043583 | August 27, 1991 | Robinson |
5666395 | September 9, 1997 | Tsukamoto et al. |
6272207 | August 7, 2001 | Tang |
6361735 | March 26, 2002 | Venkataramani et al. |
20010011709 | August 9, 2001 | Riedner et al. |
20030026386 | February 6, 2003 | Tang et al. |
20040178347 | September 16, 2004 | Murayama et al. |
195 02 574 | August 1996 | DE |
197 09 690 | September 1998 | DE |
100 42 608 | March 2001 | DE |
Type: Grant
Filed: Mar 7, 2003
Date of Patent: Jul 3, 2007
Patent Publication Number: 20050167601
Assignee: Siemens Aktiengesellschaft (Munich)
Inventors: Herbert Bruder (Höchstadt), Thomas Flohr (Ühlfeld), Karl Stierstorfer (Erlangen)
Primary Examiner: David Porta
Assistant Examiner: Christopher Webb
Attorney: Harness, Dickey & Pierce, P.L.C.
Application Number: 10/507,896
International Classification: G01T 1/20 (20060101);